Airworthiness Directives; Boeing Model 737-600, -700, -700C, and -800 Series Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 737-600, -700, -700C, and -800 series airplanes. This AD requires inspecting/measuring the length of the attachment fasteners between the nacelle support fittings and the lower wing skin panels, and related investigative/corrective actions if necessary. This AD results from a report from the manufacturer that in production, during the installation of certain attachment fasteners for the nacelle support fittings, only one washer was installed instead of two. We are issuing this AD to prevent inadequate fastener clamp-up, which could result in cracking of the fastener holes, cracking along the lower wing skin panels, fuel leaking from the wing fuel tanks onto the engines, and possible fire.